Resolution

Verify desired module is enabled for user

From within CSS Administration the administrator should navigate to User Administration and then locate the desired user
Click Edit
Click Citizen and verify that the desired module is enabled for the user, e.g. General Billing
Click Update

Verify Allow partial payments is enabled for desired module

From the menu on the far left, click Citizen Administration > Payments > Bill Categories
Next to the desired module, click Edit
Verify that Allow partial payments is checked
Click Update

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